Rubber formulations used in various tire components previously have been designed using conventional processing oils to soften and extend the rubber. Typically, aromatic processing oils, having a certain content of polycyclic aromatic (PCA) compounds or polyaromatic hydrocarbons (PAH), have been used.
For example, such extender oils may be used to reduce the Mooney viscosity of synthetic rubber to ease their compounding with other ingredients of rubber mixtures. Additionally, these extender or process oils may be used in the tire industry as processing aids to ease compounding of the rubber and as a plasticizer to modify the mechanical properties of the rubber compound after vulcanization. These extender oils may also be used to influence the visco-elastic properties of a tire compound. The aromatic content of the extender oil may enhance wet grip properties. The nature of the oils used in extending synthetic rubber and processing rubber compounds is the same.
Mineral oils are classified by their type: Aromatic, Naphthenic and Paraffinic. Most commonly used are distillate aromatic extract (DAE) oils that are processing oils with a high polycyclic aromatic hydrocarbon (PAH) content. These DAE oils are considered to have a negative impact on the environment and human health because of the PAH content. Recently, regulatory, environmental and social concerns have necessitated the use of processing oils having a lower PAH content. As a result, there is a desire for the rubber and tire industry to cease the use of process oils that contain more than 3% PAH. It has been estimated that the tire industry will face major challenges, as switching from DAE will require about a million metric tons of DAE to be replaced per year.
To replace these oils the tire industry has started to use Treated Distillate Aromatic Extract (TDAE) and Mild Extract Solvate (MES) oils. Both of these oils provide tires that have better rolling resistance but, unfortunately, worse wet grip properties. Residual Aromatic Extract (RAE-) oils are offered as another possible replacement, and these oils provide better wet grip properties than the other oils with at least as good rolling resistance properties.
However, in changing to the use of the lower PAH content oils some loss in rubber compound performance has been noted. In order to provide such low PAH content oils, it is therefore necessary to develop new rubber compounds that provide desirable performance levels while incorporating the use of low PAH oils.
The most commercially desirable replacement oils that meet this specification will generally provide tires with lower wet grip. Most of the new oils are still based on non renewable mineral oils.
U.S. Pat. No. 2,483,797, issued Oct. 4, 1949, to Edward A. Van Valkenburgh, discloses tall oil acid composition. This invention relates to improvements in tall oil compositions for use in the compounding and vulcanization of rubber.
U.S. Pat. No. 2,578,955, issued Dec. 18, 1951, to Edward A. Van Valkenburgh, discloses composition of tall oil and aromatic oil and method of making it. This invention relates to compositions for use in the compounding and vulcanization of rubber, and particularly of synthetic rubber, and to method of producing such compositions.
U.S. Pat. No. 2,657,147, issued Oct. 27, 1953, to Edward A. Van Valkenburgh, discloses composition for vulcanizing rubber. The invention relates to improvements in tall oil acid compositions useful in the compounding and vulcanization of rubber.
U.S. Pat. No. 2,843,643, issued Jul. 15, 1958, to Gleim, discloses rubber containing demethylated wood tar distillate, and a method of preventing the cracking of rubber due to attack by ozone.
U.S. Pat. No. 3,157,609, issued Nov. 17, 1964, to McNay et al., discloses treatment of synthetic rubber. More particularly, it relates to a method of improving the processing characteristics of synthetic rubber-like polymers and the products obtained thereby.
U.S. Pat. No. 3,632,855, issued Jan. 4, 1972, to Halbrook, et al., discloses rosin-fatty olefin epoxide reaction products, formed by the reaction of one mole of rosin acid with one mole of a fatty olefin epoxide to give a hydroxy ester, useful as a tackifier in styrene-butadiene rubber (SBR).
U.S. Pat. No. 3,474,059, issued Oct. 21, 1969 to Body, discloses tackifier compositions for elastomeric olefin polymers for use in providing tack in rubbery copolymers of ethylene and another copolymerizable monomer selected from a-mono-olefins such as propylene (rubbery copolymers of ethylene and propylene being sometimes referred to in the art as “EPR”) and in sulfur vulcanizable unsaturated rubber-like interpolymers of ethylene, at least one other copolymerizable monomer selected from a-mono-olefins, and at least one non-conjugated hydrocarbon diene; and to the rubbery compositions comprised of the novel tackifier composition and at least on of the above-described rubber-like copolymers and interpolymers.
U.S. Pat. No. 3,649,580, issued Mar. 14, 1972, to Arlt, Jr., et al., discloses tall oil pitch tackifiers in ethylene-propylene terpolymer rubber, containing at least 75% and preferably 80% to 100% of nonvolatile material is incorporated into ethylene-propylene terpolymer rubber, preferably as a 40% to 90% solution in rubber processing oil.
U.S. Pat. No. 3,873,482, issued Mar. 25, 1975 to Severson et al, discloses a process by which commercial tall oil materials, a mixture of fatty acids and resin acids, are pyrolyzed in a hot tube to yield products which when added to a synthetic rubber composition improve its tack.
U.S. Pat. No. 4,272,419, issued Jun. 9, 1981, to Force, discloses treatment of styrene-butadiene rubber. The adhesion and tack properties of styrene-butadiene rubber (SBR) are improved by replacing from 1% to 25% of the rubber with saponified tall oil pitch, based on the dry weight of the SBR. The SBR may be carboxylated or uncarboxylated, filled or unfilled.
U.S. Pat. No. 4,581,400, issued Apr. 8, 1986, to Kondo, discloses rubber compositions modified with blends of rosin material. A rubber composition comprising (a) 100 parts by weight of a rubber selected from the group consisting of natural rubber and synthetic diene rubbers and (b) about 1 to about 30 parts by weight of a rosin derivative comprising a blend of (i) about 15 to about 50% by weight of a rosin, (ii) about 10 to about 70% by weight of a polymerized rosin and (iii) not more than about 55% by weight of a rosin pitch, each based on the weight of the rosin derivative.
U.S. Pat. No. 5,504,135, issued Apr. 2, 1996, to Ardrizzi, et al., discloses an oil composition which has a kinematic viscosity at 100 C of from 32 to 50 cSt and which contains less than 3 weight percent polynuclear aromatic compounds that is employed as a process oil for rubber compounds, especially aromatic rubbers.
U.S. Pat. No. 6,103,808, issued Aug. 15, 2000, to Hashimoto, discloses a high aromatic oil and rubber composition and oil extended synthetic rubber using the same.
U.S. Patent Publication No. 2001/0023307, published Sep. 20, 2001, to Kaimai et al., discloses a rubber process oil in which the content of polycyclic aromatics (PCAs) as determined by the IP 346 method is less than 3% by mass and which is rich in aromatic hydrocarbons, and a method for producing the same
U.S. Patent Publication No. 2002/0045697, published Apr. 18, 2002, to Sohnen et al., discloses a sulfur vulcanizable rubber composition which does not contain aromatic process oils including at least one diene elastomer, at least finely dispersed, precipitated silica and carbon as fillers, softeners, at least one silane coupling agent, and additional common additives as well as a process for their production.
U.S. Patent Publication No. 2002/0000280, published Jan. 3, 2002, to Scholl, discloses rubber mixtures for producing highly reinforced vulcanizates with low damping behaviour. The rubber mixtures consist of a rubber, a filler and a specific sulphurized mineral oil and are suitable for producing shaped vulcanizates, in particular for producing tires with reduced rolling resistance and high resistance to wet skidding, and tires with particularly reinforced side walls (“run flat tires”).
U.S. Pat. No. 6,399,697, issued Jun. 4, 2002, to Takasaki, et al., discloses a process oil which satisfies requirements that a content of a polycyclic aromatic compound is less than 3% by weight, a content of an aromatic hydrocarbon is 18% by weight or more, a content of a polar compound is between 11 and 25% by weight, a kinematic viscosity at 100 C is between 10 and 70 mm2/s, and a flash point is 210 C or more.
U.S. Pat. No. 6,984,687, issued Jan. 10, 2006, to Henning, et al., discloses an oil extended rubber and composition containing low PCA oil.
U.S. Pat. No. 7,193,004, issued Mar. 20, 2007, to Weydert, et al., discloses a pneumatic tire having a component containing low PCA oil
U.S. Patent No. 2007/0082991, issued Apr. 12, 2007, to Chassagnon, et al., discloses tread for pneumatic tires. The invention relates to a tread for pneumatic tires with an improved capacity for adhesion to wet ground. Said tread consists of a rubber composition containing at least: (i) one dienic elastomer comprising more than 30 parts of rubber butyl, (ii) a reinforcing inorganic load such as silica, (iii) a coupling agent for the inorganic load, and, as a plasiticising agent, (iv) a glycerol unsaturated fatty acid triester (C12-C22), especially a glycerol trioleate.
However, in spite of the above advancements, there exists a need in the art for tire materials, tire compositions, tire components tires comprising such components and compositions, and methods of making and using such materials, compositions and tires.
There is a need in the art for a process oil that is not reliant on fossil based fuels and also provides the same level of performance as current process oils.
These and other needs in the art will become apparent to those of skill in the art upon review of this specification, including its drawings and claims.